Butterfly Labs - Bitforce Single and Mini Rig Box

[wogaut]

Question to BFL (or anyone else who has attempted this):

I notice that some of the Rev3 (heatpipe) Singles are shipping with a small fan on the bottom of the PCB, while others do not have that fan (only a passive circular copper heatsink). I'm assuming that the bottom fan on certain units is to give them a bit more thermal headroom.

My question is: How necessary is that bottom fan to the operation of the Single? If the unit is in a cool environment (<72F), and the bottom fan is disabled, would the unit be likely to throttle?

I ask because both the top and bottom fans are fed from the same 12V cable; if I ever decide to change the top fan for something else (say it fails), I'd have to either rewire the connection to the bottom fan (a pain), or loose the bottom fan.

Well, here's the classic BFL answer to this type of question:

Silicon is an organic process giving each chip it's own personality.  In the case of the singles, their operational heat signature is slightly different from unit to unit.  As we test them, we may place a fan under some units to increase it's thermal range.  You can take the fan off if you like.

I should also point out that faster firmware (when released) will perform more reliably in cooler environments.  

That answer related to the extra fan underneath the case on some rev 3 units, but I would think that it's also the answer to your question.

[Inaba]

Epoch:  You can remove it if your room is cooler.  It's there to, as you surmised, give it more headroom at that hashrate.  There's no harm in removing it; try it and see if your unit throttles.

[Epoch]

Yes, I will try that on one my units shortly. I'll have to snip the leads to the bottom fan, as the same power connector feeds both top and bottom fans and there doesn't seem to be an easy way to detach power from the bottom fan independently.

Unfortunate; the Rev2 units had 2 independently powered fans (and there are 2 fan headers on the PCB, even the Rev3 ones) so they were easy to swap out. The Rev3 units seem to power both fans from the same cable which makes things easier for assembly, but uglier for maintenance.

[rjk]

Yes, I will try that on one my units shortly. I'll have to snip the leads to the bottom fan, as the same power connector feeds both top and bottom fans and there doesn't seem to be an easy way to detach power from the bottom fan independently.

Unfortunate; the Rev2 units had 2 independently powered fans (and there are 2 fan headers on the PCB, even the Rev3 ones) so they were easy to swap out. The Rev3 units seem to power both fans from the same cable which makes things easier for assembly, but uglier for maintenance.

I don't know what brand of fans your unit has, but the ones in mine have a detachable connector at the motor hub as well as at the plug end.

[Epoch]

I don't know what brand of fans your unit has, but the ones in mine have a detachable connector at the motor hub as well as at the plug end.

BFL doesn't seem to have a 'standard fan' they use consistently. Some of my units have an OEM Panaflow, some have a Sunon, and the latest batch has a 'no-name' fan. This is for the top 92mm fan.

For my Rev3 units with a 2nd fan attached to the underside of the PCB, I haven't taken a close look at it yet since I need to remove the PCB from the case (a pain). It is very small (40mm?), low-profile, and spins inside a heatsink. It is visible when looking through the ventilation holes at the bottom of the case.

I'll certainly take a closer look, but I know these 2-fan Rev3 units have a single fan cable harness in a Y-configuration; a single connector powering both fans plugs into a single PCB header. One pair of leads goes to the top fan while the other pair goes to the bottom fan. I believe the cable leading to the bottom fan is non-detachable at the fan end, but I'll confirm that. It would be great if it were detachable.

[WhitePhantom]

I'll have to snip the leads to the bottom fan

For simplicity in testing, I'd recommend just taping down the fan blade to keep it from spinning, or another low-tech method of restriction (a piece of chewed gum?).  If you get some thermal throttling, it's easy to make it spin again.

[Epoch]

I'll have to snip the leads to the bottom fan

For simplicity in testing, I'd recommend just taping down the fan blade to keep it from spinning, or another low-tech method of restriction (a piece of chewed gum?).  If you get some thermal throttling, it's easy to make it spin again.

Good point. 

[Inspector 2211]

I'll have to snip the leads to the bottom fan

For simplicity in testing, I'd recommend just taping down the fan blade to keep it from spinning, or another low-tech method of restriction (a piece of chewed gum?).  If you get some thermal throttling, it's easy to make it spin again.

I would advise against that - a stuck motor can draw a multiple of the wattage that it normally draws, and thus overheat, even burn out.

[coblee]

I finally got my BFL singles. I can't quite get them mining.

Does a solid red light mean it's working properly or not?

Does anyone have success running these on a mac? Do you run cgminer or MPBM or something else?
Do they show up as /dev/tty.usbserial?

[Epoch]

I finally got my BFL singles. I can't quite get them mining.

Does a solid red light mean it's working properly or not?

Does anyone have success running these on a mac? Do you run cgminer or MPBM or something else?
Do they show up as /dev/tty.usbserial?

Sorry, Coblee, can't help you about the Mac. But a solid red light is a good sign. There are actually 3 LEDs on a Single (from memory; I don't have one in front of me ATM). There is 1 external one and 2 internal ones:

External LED:
solid: unit is ready to mine, or is mining
blinking: unit is booting up (takes about 10 seconds from power-on), or is thermally throttling

Internal LED #1:
always solid on: unit is powered

Internal LED #2:
off: unit is idle and not mining
solid on: unit is mining
(this LED will blink once every 5.2 seconds, after it finishes its nonce range and gets new work)

[TheSeven]

I'll have to snip the leads to the bottom fan

For simplicity in testing, I'd recommend just taping down the fan blade to keep it from spinning, or another low-tech method of restriction (a piece of chewed gum?).  If you get some thermal throttling, it's easy to make it spin again.

I would advise against that - a stuck motor can draw a multiple of the wattage that it normally draws, and thus overheat, even burn out.

Well, a piece of paper across the air intake should do the trick for testing, but I generally advise against trusting in any kind of thermal shutdown, especially if the unit is known to not have on-die temperature sensors and just measure the board/air/case temperature.

[rjk]

I'll have to snip the leads to the bottom fan

For simplicity in testing, I'd recommend just taping down the fan blade to keep it from spinning, or another low-tech method of restriction (a piece of chewed gum?).  If you get some thermal throttling, it's easy to make it spin again.

I would advise against that - a stuck motor can draw a multiple of the wattage that it normally draws, and thus overheat, even burn out.

Well, a piece of paper across the air intake should do the trick for testing, but I generally advise against trusting in any kind of thermal shutdown, especially if the unit is known to not have on-die temperature sensors and just measure the board/air/case temperature.

The singles do have on-die temp sensors, and they can be read with cgminer.

[Tinua]

I read allways that the BFL-Singles need ~80Watt.

My PC with 1 mining GPU HD5770 and 15 BFL-Singles v3 suck ~920 Watt from the wall.
My PC and GPU need 180 Watt; the 15 BFL's need 740Watt.
This give only ~50Watt/Single ; this with the orginal China-Powersupply.  

Or is something wrong with my measurement?

 

[SgtSpike]

What are you using to measure?

[rjk]

I read allways that the BFL-Singles need ~80Watt.

My PC with 1 mining GPU HD5770 and 15 BFL-Singles v3 suck ~920 Watt from the wall.
My PC and GPU need 180 Watt; the 15 BFL's need 740Watt.
This give only ~50Watt/Single ; this with the orginal China-Powersupply.  

Or is something wrong with my measurement?

 

It is possible that newer versions may be doing better on power usage, since the measurements were made with older models. But as far as we know, only the cooling components have changed in the newer versions. What are you using to measure the power draw?

The only other change that I know of was that the board was slightly changed to support the heatpipe mounting system - perhaps the power subsystem got a tweak at the same time to improve efficiency.

[Tinua]

What are you using to measure?

I know its not exactly...but 40% wrong
Beside...i use also an other model...same result +/-

[The00Dustin]

I read allways that the BFL-Singles need ~80Watt.

My PC with 1 mining GPU HD5770 and 15 BFL-Singles v3 suck ~920 Watt from the wall.
My PC and GPU need 180 Watt; the 15 BFL's need 740Watt.
This give only ~50Watt/Single ; this with the orginal China-Powersupply.  

Or is something wrong with my measurement?

It has been a long time since I have taken an electronics class, but I believe wattage would be lower if voltage was higher.  If you were running on 220, then that might explain it.  I believe you mentioned German Windows in another thread, so I thought you might be in Europe and figured I'd point this out.

[Tinua]

I read allways that the BFL-Singles need ~80Watt.

My PC with 1 mining GPU HD5770 and 15 BFL-Singles v3 suck ~920 Watt from the wall.
My PC and GPU need 180 Watt; the 15 BFL's need 740Watt.
This give only ~50Watt/Single ; this with the orginal China-Powersupply.  

Or is something wrong with my measurement?

It has been a long time since I have taken an electronics class, but I believe wattage would be lower if voltage was higher.  If you were running on 220, then that might explain it.  I believe you mentioned German Windows in another thread, so I thought you might be in Europe and figured I'd point this out.

Yes..I'm from Swiss.
We have 230V.
What I know is wattage is allways the same. The Ampere go down (P=UxI)
If the Powersupply only suck 50Watt by 230V (0.21A), then it can not give more by 12Volt. Only the Ampere go up to 4.16A.
(Not including the inefficiency of the China-Powerupply)

Or I'm wrong?

[SgtSpike]

I read allways that the BFL-Singles need ~80Watt.

My PC with 1 mining GPU HD5770 and 15 BFL-Singles v3 suck ~920 Watt from the wall.
My PC and GPU need 180 Watt; the 15 BFL's need 740Watt.
This give only ~50Watt/Single ; this with the orginal China-Powersupply.  

Or is something wrong with my measurement?

It has been a long time since I have taken an electronics class, but I believe wattage would be lower if voltage was higher.  If you were running on 220, then that might explain it.  I believe you mentioned German Windows in another thread, so I thought you might be in Europe and figured I'd point this out.

Yes..I'm from Switzerland.
We have 230V.
What I know is wattage is allways the same. The Ampere go down (P=UxI)
If the Powersupply only suck 50Watt by 230V (0.21A), then it can not give more by 12Volt. Only the Ampere go up to 4.16A.
(Not including the inefficienc of the China-Powerupply)

Or I'm wrong?

No, you are correct.  Wattage remains the same regardless of what voltage you are running at.  Higher voltage just means lower amperage needs to be drawn to equate to the same wattage.

[ice_chill]

They changed the power phase in REV3, it looks like a much more efficient one.